State Street Global Advisors is one of the most recent of those voices, proposing that lawmakers mandate guaranteed access to a retirement savings platform that all employers would be require to offer through auto-enrollment.

The State Street plan would include part-time workers — who currently account for a massive gap in retirement savings. Extending retirement savings opportunities to part-timers, as well as others who work “limited hours or seasonally,” was also a “best practice” recommended, among others, by the Bipartisan Policy Center’s Commission on Retirement Security and Personal Savings.

The commission was also critical of individual efforts by states to create retirement plans, because they result in a “patchwork” of rules and coverage — for instance, on the matter of mandatory coverage; some state measures, though not all, require employers to auto enroll workers into a plan. In Connecticut, the plan is a Roth IRA. And all the proposed auto-enroll mandates come with an opt-out feature.

But it is likely to take more than simply extending auto-enrollment to everyone, if Vanguard figures accurately reflect the situation; while auto enrollment certainly ups the number of participants, the account balances are smaller — and they’re already insufficient for most people to make it through retirement without some other source of income.